Impact of closed versus open venous reservoirs on patient outcomes in isolated coronary artery bypass graft surgery

Data were collected retrospectively on 1,681 consecutive isolated coronary artery bypass graft patients at Millard Fillmore Hospital (Buffalo, New York, USA) undergoing coronary artery bypass. No patients were excluded. There were 616 patients in the open circuit group and 1,065 in the closed circuit group. Patients in the closed circuit group exhibited a trend towards a higher incidence of most pre-existing comorbidities, with acute myocardial infarction, pre-existing cerebrovascular disease and the incidence of extensively calcified aortas all being significantly higher. Significantly different postbypass outcomes favored the closed circuit group, with levels of sepsis of 1% for open and 0% for closed and respiratory failure of 4% for open and 1% for closed. The length of stay approached significance with a p-value of 0.057 (open 9.85 days and closed 7.53). Use of an open circuit was a significant, independent predictor for increased use of units of packed red blood cells and total units of blood products. This study provides evidence that closed venous reservoirs can favorably impact surgical outcomes and reduce resulting healthcare costs.